the anagama. adopted by the japanese from china when there were no horses in north america, crazy i know. they are primarily used for high fire, temperature-over-time, heavy ash build up ceramic objects. can yield good stuff. a firing takes typically four to seven days but one might hear of 10 to 15 day firings. originally built into the sides of earthen hills and fired with no pyrometric cones, the word anagama truely means 'cave fire,' the early masters of the fire used the sound of the roaring fire, the color of the flame, and the intesity of the heat. the process today has a very powerful effect on those who experience it just once. there really isn't anything that can compare to the whole process. calculated. chaotic. scientific. spiritual.
oh for a great reference book, coffee table book for the person who likes pots, bedside bible for the wood-thirsty flaming beast in all of us, and all the explainations and names for marks made by the kiln gods and you; great images. check out 'Japanese Wood-Fired Ceramics' by Masakazu Kusakabe and Marc Lancet.